Perhaps you should try some spelling variations:
tru nang » tra nang, tri nang, truc nano
hieu van » hieu va, thien van, lieu va
van hanh » van thanh, ban hanh, van anh
tu sach » thu sach, su sach, te sach
tu nang » tu nong, tu nano, tu lang
nam qua » nam quan, nam cua, nam mua
qua van » quan van, qua ban, qua san
hanh va » hang va, hanh vi
cau tre » cau tren, cau treo, cau tra
va cau » van cau, va cac, va dau

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ((tu nang) or (tru nang)) xa hoi. hieu van nam qua van hanh va cau tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((tu nang) OR (tru nang)) xa hoi. hieu van nam qua van hanh va cau tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ((tu nang) or (tru nang)) xa hoi. hieu van nam qua van hanh va cau tre*.